HAZOP (Hazard and Operability Study)
HAZOP study is a systematic way to identify hazards in the system, find causes, consequences and existing safeguards. If the safeguards are not adequate recommendations are given to mitigate the risk.
HAZID (Hazard identification)
HAZID is similar to HAZOP. The only difference is HAZOP is carried out on P&IDs and considers only operability hazards whereas HAZID is conducted on various documents and all possible hazards including natural calamities are discussed.
Process Hazard Analysis
This is hazard identification study where all possible process hazards are identified and listed.
Traditionally, safety in the design of chemical plants relied upon the application of codes of practice, design codes and checklists based on the wide experience and knowledge of professional experts and specialists in the industry. However, such approaches can only cope with problems that have arisen before. With the increasing complexity of modern plant, these traditional approaches are likely to miss other issues which need to be considered. Hazard
and Operability Studies (HAZOPs) were developed by ―Imperial Chemical Industries‖ during the 1960s as a technique to overcome this problem and to systematically identify potential hazards and operability problems in new designs for chemical and petrochemical plant, in both batch and continuous processes. HAZOPs can also be used for modifications and for the review of existing processes.
Significance of HAZOP
HAZOP is particularly useful for identifying weaknesses in systems (existing or proposed)
involving the flow of materials, people or data, or a number of events or activities in a
planned sequence or the procedures controlling such a sequence. As well as being a valuable
tool in the design and development of new systems, HAZOP may also be profitably
employed to examine hazards and potential problems associated with different operating
states of a given system, e.g. start-up, standby, normal operation, normal shutdown and
emergency shutdown. It can also be employed for batch and unsteady-state processes and
sequences as well as for continuous ones. HAZOP may be viewed as an integral part of the
overall process of value engineering and risk management.